Typewriting machine



Dec. l5, 1931.

3 Sheets-Sheet Filed Jan. 16, 1928 N N# m. YM Wlflmallllh M o Ii? w T m m m MIF-.PNJ WNEDO-m T @@@QQQQ 1 @@@wm Dec. 15, 1931.' w A DOBSON 1,837,025

TYPEWRITING MACHINE Filed Jan. 16, 1928 3 Sheets-Sheet 2 l I INVENTOR:

. ATTO EY.

Dec. 15, 1931.

TYPEWRITING MACHINE `Filed Jan. 16, 1928 3 Sheets-Sheet 3 FIG. 7.

w. A. DoBsoN 1,837,025 I Patented Dec. 15, 1931 UNITED STATES PATENTfoI-frlca WILLIAM A. DoBsoN, or Viinrnennonr, CONNECTICUT, Y AssIGNon To UNDEnwoon ELLIQTTFISHEB COMPANY, oF NEW Yoann. Y., a conPoRATIoN or DELAWARE Y TYPEWRITING MACHINE Application nieu January 16,1928. serial No. 247,018.

This invention relates to machines for'typing words together with numerals and fr aetions, and one of the objects ofthe invention is to simplify a machine in which it 1sA desired to use an excessive number, of fractions and special characters, that is, more than can be accommodated in an ordinary four-bank typewriter having a single case-shaft.

According to the present invention, there is used only a single shift and the keyboard has a system of alphabet-keys all connected to print capital? letters, `and'it also has on'the same keys a system of numerals and a 'system of fraction-characters, and' punctuation and other marks, giving aV great range or flexibility in typing numbersand fractions, especially for monetary and other purposes.

One of the features of the invention is'in the nature of means for avoiding the taxing of the mindV ofthe operator in remembering to shift-the platen up anddown for letters or figures as the case may be,\said shifting being necessarily frequent where every typed word' is followed` by a typed number, that is,

'i where words and numbers alternate across the page in the line of writing,rwhich is a use for which this machine is especially suitable. It willbe understood that, if an attempt should bemade to effect such a result with an ordinary'four-row typewriter, even though it printed no lower-case letters,there would need to be much shifting done and much study of the keyboard in connection with the shifting owing to the fact that a sin le set of keys comprising four rows Vwould e insuflicient to ,carry a complete alphabet and a complete setfof` numerals, fractions and punctuati'ons on the same shift, and the use. of the shift-key onv such a machine would nec-A essarily be difficult and tiresome, and liability of errors wouldfbe great where it was desired to write words and numbers alternately along the line of Writing across the page.`

vAccording to the present invention, asinele-shift machine is employed, and twenty six keys are'de'voted to capitals on one shift nd the same key's'are devoted to numerals. fractions and punctuation marks on the other shift. There may be also three other keys, auch having two appropriate types.

vIn using this machine, the keys are operated first to type a wordi and then the operator` depresses a space-bar to secure a'space' after the word on the work-sheet, and, in so doing, 'he automatically shifts the machine so thatY numerals, fractions andpunctuationmarks will be typed at the next operations of the type-keys.4 The machine isnow used for `typing the numbers. Having completed the numbers the operator again uses a spacebar to space the numbers fromthe succeedving word on the work-sheet, and, in so doing, he automatically resets the machine for writingletters. So the work proceeds, words alternating with numbers, using theV different shift-positions of the typewriter alternately and automatically without any special attention on the part of the operator, thus avoiding errors and greatlyexpediting the work. p p

- For the purpose of the invention, the wordspacing of the machine is effected by means of either one of two spacebars,one of -which is operated after typing aword, and the other of which is operated Vaftertyping a atively connected Vto appropriate case-shifting 75 number. One of thesespace-bars is oper-- mechanism, which co-operates with a releasi able latch'for automatically latchingthe caseshifting mechanism in upper-case position. The othervspace-bar releases the latch.V

The machine is also capable of writing :i

succession of wordsto form a line, the same as in a usual typewriter, and in this case the operator uses that one of the two spacebars which has been arranged for use `afterv writing figures. That is, he uses-the typekeys towrite the word, Aand then uses "one,

space-bar if he Vexpects to write another word Y i Y immediately, or the other space-bar if he expects to write a number immediately. v Each of the space-bars will affect the letter-space mechanism, but where an operator desires to Y write a succession of words he uses the spacebar which -doesnotaffect 4 the shift-mechanism. i" i Other features and advantages will hereinafter appear.

, 'In the accompanying drawings,

Figure 1 is a fragmentary cross-sectional view, front to rear, through a typewriting machine having my invention applied thereto.

Figure 2 is a detailed view illustrating means of adjusting the locking pin for the platen-shifting mechanism.

Figure 3 is a plan view of a keyboard suitable for use in typing telegrams and other communications relating to monetary transactions.-

Figure 4 is a fragmentary cross-sectional view, front to rear, of the structure shown in Figure 1, the platen-shifting space-bar being illustrated in operated position and the shift-frame locked in upper-shift position.

Figure 5 is a view similar to Figure 4, the shift-frame-releasing space-bar being shown in operated position and the platen-shiftframe shown at the moment of beginning its descent to normal position.

Figure 6 is a fragmentary top view of mechanism operatively connecting the space-y barswith the escapement-mechani sm.

Figure 7 is a fragmentary perspective view of the space-bars of the-invention and interponents for operatively connecting them with the escapement-mechanism .and the platenshift-frame of the typewritingmachine.

The present invention may be applied to a portable typewriting machine, which is in general similar to that .disclosed in a patent granted` to me, No. 1,335,956, `datedApril 6, 1920.VV Each of a pluralityof type-bars 10 may have a numeral typel 11 and a capital letter type 12, and may be swung against a platen 13 by 'depression of a key 14 operatively connected with a type-bar by usual instrumentalities not shown. The Vplaten is mounted on a platen-shaft 15` journaled in end plates 16'of a sheet-metal carriage 17,

which may be pulled tothe left by a usual spring, not shown,` under control of escapement-mechanism generallyvdesignated as 18.

The carriage travels on rollers 20 and ballbearings 21 which run-on tracks 22 and 23 respectively, the tracks being fastened rigidly between side plates 24 of'a shift-frame generally-designated as 25NA For guiding the shift-frame, each of the side plates is pivotally fastened adjacent its forward side to the forward end of a long rearwardly-artending arm 26, whose rear end is pivoted on a stud 27 in the main frame 28. 24 is-pivotallv connected adjacent its lower edge and in the rear of the forward lend of the arm 26 to a stud- 29 in the forward end of a rockingarm 30, which is securely fastened on a lateral rock-shaft 31 ournaled in the mainframe V28. The escapement-mechanism 18V-includes a raclr 32 fastened on the carriage 17 and meshing with a pinion 33, which is fastened toan escapement-wheel 34. A dog-rocker 35 carries a loose dog 36 and a fixed vdog 37, bothofv which are mounted for operatively engaging the escapeinent-wheel Also eachside platel 34, so as to permit 'it to rotate a step at a time. The construction and operation of the escapement-mechanism 18 may be the same as that disclosed in Patent No. 1,332,972, granted to George 1V. Campbell March 9, 1920.

For bringing the platen 13 to position for engagement with a numeral type l1, which is indicated by a dot-and-dash position in Figure 4, the shift-frame 25 is swung upwardly on the arms 26 and 30 hy rocking the shaft 31 clockwise. A forwardly-extending operating arm 38 is fastened rigidly on the shaft 31 adjacent the left end thereof, and has a laterally-hent tab 39 atits forward end.

In typing certain .data relating to monetary transactions, it is common in some offices to alternately type a group of letters and a group of figures with the usual spacing between the groups. To reducethe number of platen-shifting operations required in typing such data, there is provided in the machine embodying the present invention a left-hand and a right-hand spacebar 40 and 41, respectively, which are positioned ,inl lateral aligrnent with each other'at the front of the usual keyboard each of whicliroperates the escapement-mechanism 18 and has an operative connection with theplaten-shift mechanism of the machine. The space-bar 41 is carried by a right-handand a left-hand space-bar-lever 42, 43, the rear enddof each lever vbeing fastened rigidly to a rock-shaft 44, whoseright end is journaled in a depending car 45 on a right-hand side plate 46 of the main frame 28. .y The left end of the shaft 44 is journaled in a right-hand ear 47 of a bracket-plate 48, which may be fastened by screws 49 to a usual key-lever guide-comb 50, which is positioned between' the right-hand side plate 46 and aI left-hand side plate 51 of the main frame.

It is found desirable to shift the platen 1,3 upon depression of the space-bar v40` and, to that end, interponents between the latter andthe arm 38 are provided, as follows: two space-bar-levers 52 carry the space-bar 4() on their forward ends, and have their rear ends fastened to a rock-shaft 53, whose rightend is journaled in an ear 54 of` the bracket 48 and'whose end is journaled in a depending flange 55 on the side plate 51. An upwardlyextending rock-arm 56, fastened rigidly on the shaft 53, carries an inreaching lateral pin 577 on which is loosely mounted a roller 58, which arrangement swings the roller counterclockwise upon .depression ofthe space-bar 40. A lever 59 extending Vfrom an engagement with the roller 58 to the tab 39 is pivoted therebetween on a stud 60 in an integral standard 61 on a cross-bar 62, which is fas tened between the side plates 46 and 51. The upper edge of a forward portion 63 of the lever 59 is disposed against the lower side of the roller 58 and curves upwardly and forwardly in front of the same with a radius and, when the space-bar 40 is depressed, the

roller 58V is swung forward and ,cams the forward end of the lever 59 down, and swings the. tab 39 up, thus rocking the shaft 81 and raising the platenl to upper-shift posi-A tion, which is determinedlby an inturned;

flange 64- on each side' plate 24 striking against a screw 65 held in anl upwardly-- extending bracket 66 of a mounting plate 67 which maybe riveted to a rearcross-bar 68 fastened between the. side plates, 46 and 5.1 of the main frame 28. A screw 69 through he forward end of each mounting plate 67' engages the adjacent fiange 64 and deter mines the lower-case or normal position of the platen.l T he stop-screws 65 and 69 are each provided with a lock-nut 7 0.

The upwardly-curved forward portion 63 of the leverl 59 also serves as a stop to arrest the forward movement of the roller, and the f downward movement of the space-bar 40,` as

can be readily seen from inspection of the relative positions of the roller 58, the lever 59 and the arm 56, as shownin Figure 4.

ToA lock the platen in upper-caseposition,

g a laterally-extending pin 71 is fastened in the rock-arm 38 a short distanceto the lrear of the rear end ofthe lever 59. A locking trigger or prop, generally designated as 72, is pivotally mounted Ona stud 73 screwed into an upturned `fiange 74 of a mounting plate 75 fastened by rivets 76 to the bot-tom side of the cross-bar 62.` The trigger 72 has an wrightbody 7 7 and anV integral rearward y-extending elbowed arm: 78 at the upper end of the body 77. A concave lock- Y ing notch 80k is cut out of the trigger at the intersection of the upper edge ofthe arm 78 and the forward edge of the'Luoright` body-member 77. A tensile spring 81, which has its; rear end fastened to a tongue 82. on

thebody 7 7 and its forward end fastened to a. pin 831 in the ange 74 tends to swing the trigger 72 forwardly. .In Figure 1 is shown the normal or ineffective position. of the trigger, whose forward edge is urged against the pin 71 in the rock-arm 38.` It will be" readily seen from an inspection of Figures 1, 4 and 5 that, upon depressing the space-har 40K and eoncomitantly raisin-g the arm 38, the pin 71 will ride up along the forwardedge of the upright trigger-body 77funt1l 1t rea-ches the notch 80, when the trigger-body will be snapped forwardly by the spring 81 and the Vnotch seated against thepin, as shownin Figure 4,. which engagement operates as a propV to; support the weight of the platen and shift-frame and prevents the returnto normal of the shift-iframe operating arni-38 .upon release of the space-basr140. v 'Y For operating the eSeapeMent-meehanism 18 bythe space-bar 40 an operative connection is provided between the two elements including an upwardly-extending inverted L- shaped actuator-member 84 fastened on the shaft 53 a short distance to the right from thexarm 56. A rearwardly-extending armportion 85'of the actuator is provided with a lengthwise slot V'86. The actuator is urged toward the rear by a spring 87, which has one end fastened to a depending ear 88 of the arm 85, and the otherv end to a rearwardlyextending flange 89 integral withthe comb 50, at the bottom edge thereof. The rearmost position of the actuator is determined by the engagement against the comb 50 of a rearwardly-extending tooth v90 on a stop-arm 91, the latter being fastened rigidly on the shaft 53 on ,which the actuator is mounted. A rearwardly-extending connecting rod 92 is fastened to the actuator 84 by a clevis-like member 93, having a forwardly-extending arm 94 disposed closely against each sidev of the actuator, and a pin 95 fastened in the ends of the arms 94 and extending through the slot 86; To the rear end Vof the rod 92 is fastened a link-member 96, which has a rearwardly-extending upwardly-curved arm 97.

To operatively connect the link-member 96 with the dog-rocker 35, Figure 6, provision ismade'of a swinging member 100 herein-` after called a dog-'rocker operator which has a body 101 extending rightwardly to a point adjacent the usual left end of the dog-rocker.`

body 101 an integral wrist-member 104 bends forward and is fastened to the link 96 by a shoulder-screw 105. which passes 'loosely through a hole inthe link-member, and is threaded into the wrist 104 as a crank-pin. Toperm'it the operator 100 to swing forwardly and backwardly, it is mounted on the upiio per ends of two arms 106 of a U-shapedrocker 107, which is fastened on an axle-pin 108 journaled in two bearing-plates 109Vwhich Y are mounted on the cross-bar 68.

In the normal position vof the space-bar 40 and escapement-mechanism 18, as shown in d Figures 1 and V7,'the pin 95 is disposedv against the rear end of the slot 86. It will berseen'that a slight initial downward movement of the space-bar40'will move the'es-V capement-mechanism, and thereafterl the platen is shifted and locked in upper-case position, but the escapernent-mechanism will kthe carriage until the space- Vcapital letters, is-eflective to letter-space the platen, shift it to upper-shift position, and

lise

` ger 72, while concomitantly operating the es-v lock it therein preparatory to typing a group of numerals. After writing a group of numerals, it is desirable, according to one use of the invention, to write a group of capital letters with the Vusual Vletter-space between the groups. To position the platen with a minimum of operations for typing the lastmentioned group, means, to be presently described, are provided for making the spacebar 40 effective for releasing the locking trigcapement-mechanism. The space-bar-lever 43 has a depending ear 110, with a collar 112 fixed thereto, through which passes a lateral- V. ly-disposed shaft 111 pinned to the collar.

The shaft 111 extends leftwardly to the side plate 51 and is journaled therein, a collar 113 on the shaft holding it against leftward displacement. An inverted L-shaped rocking arm 114 is fastened on the shaft 111 a short distance to the left of the plane of the actuator 84. A spring 115, which has one end fastened to a pin 116 in vrearwardly-eXtending portion 117 of the rocking arm 114, and the other end to the flange 89, normally urges the rocking arm rearwardly, the rearmost position of the latter may be determined by the bottoming of the portion 117 in a slot in the comb 50. To malte the depression of the space-bar 41 more effective for 'turning the` shaft 111 and rocking the arm 114, the shaft may be formed'with two right-angle bends,

so as to provide a crank-like element 118 in n the shaft between the ear 110 and the arm 114 (Figure 7). Y

An operative connection between the arm 114 and the locking trigger 72 includes a rearwardly-extending connecting rod 120, whose forward end is loosely fastened to the rear end of the arm-portion 117 by-a clevis 121,

which has an arm 122 engaging against each side of the arm-portion 117 and a pin 123 fastened in the ends of the arms 122 and eX- tending loosely through a holein the armportion 117. A cam-acting plate 125 is fastened on the rear end of the rod 120, and extends rearwardly therefrom adjacent the wrist 104. The plate 125 has an enlarged rear end portion 126 provided with a downwardly and forwardly curved cam-slot 127,

which is arranged to ride upon the shoulderswing the dog-rocker operator forward with-A out affecting the space-bar 41, since, in the latter case, the screw 105 will ride idly in the slot 127. When the space-bar 41 is depressed, and the operator 100 is swung forward, the connection-rod 92 and vclevis 93 are moved forwardfbut the actuator 84 and space-bar 40 are not affected since the pin 95 in the clevis 93 will slide idly forward in the slot 86.

The lower edge of the plate 125 adjacent its forward end is arranged with a downwardly and rearwardly sloping cam-edge 128 for a purpose which will presently appear. It will be noted that, in normal position, the screw 105 is disposed a short distance in front of a vertical plane through the axle-pin 108 (Figure 1) and consequently when the spacebar 41 is depressed the screw will be swung downward as well as forward, and the camedge 128 is thereby caused to move down as well as forward. W'hen the platen-shifting space-.bar 40 is operated, the locking trigger 72, in 'a way described above, is swung forward, and a pin 129 in the rear end of the trigger-arm 78 is swung up against the camedge 128 of the pla-te 125, and remains in this position while a group of upper-shift characters or numerals are typed. The subsequent depression of the space-bar 41 causes the forward and downward movement of the camedge 128 to press the pin 129 down and swing the trigger 72 clockwise until the locking notch 80 is disengaged from the pin 71, which permits the latter and the rocking arm 38 to be restored by the weight of the carriage to normal lower-shift position. Upon release of the space-bar 41, the spring 115 is effective to return the cam-plate 125 rearwardly to normal position, and a usual spring 130 returns the dog-rocker 35 to normal, permitting the escapement-mechanism to letter-space the platen one step, the escapement-mechanism 18 is operated, and the machine is in condition to have ordinary lower-shift typing performed.

It will be noted that the advantageous arrangement of the space-bars 40 and 41 in alignment with each other at the front of the machine, to form substantially a single spacebar divided in two sections, permits the operator, at all times, to conveniently depress the space-bar 40 with the left hand and the space-bar 41 with the right hand. 1t had been found that operation of the space-bar 40 by the left hand before a group of figures, and operation of the space-bar 41 by the right hand before a group of capitals are done almost unconsciously after a short time, which makes for speed and accuracy.

In Figure 2 is illustrated an advantageous adjusting means to permit a pin 131, carried by the platen-shift-operating roll 58, to be adjusted with respect to the trigger 72, whereby the platen-shift-frame may be accurately locked in its upper-case position, as determined by the flange 64 and the screw 65. An adjusting plate or strip 132 is pivoted against the inner face of the arm 38 on screw 133 threaded lin the arm. The pin 131 is fixed rigidly in the plate 132. An integral transversely-extending lip 134- is arranged' at the forward end ofthe plate 132to' extend over the upper side of the arm 38, and is provided with a tapped hole through which is threaded an adjusting screw 135, which bears against the upper sidel ofthe arm 38". A slot 1361s arranged in the plate 132 between screw 133- and the lip 134, and is curved about the axis ofthe screw 133 Vas a center. screw 137 passes through the slot 136,fand is threaded into the arm 38 and extends therethrough to receive lock-nut 138.

Variations may be resorted to withinV Vthe scope of the invention, and portions ,of-the i improvements may bel used without' others.

Having thus described my inventin, I claim:

1. In' a single-shift typewriting machine arranged for typing letters in lower-shift position and for typing `numerals in u pershift position, thecembnaton with a p aten, an escapement-mechanism, and a platenshifting mechanism including a rock-arm with stops to limit the shift of the frame,

of a.v space-bar for operating said escapementmechanism, an operative connection betweenV said space-bar and said rock-arm effective for lifting said platen to upper-shift position upon operating said space-bar for wordsp'acing a group of letterstyped in lowershift position froman immediately followgroup of figures to be typed'in upper= shift position, a releasable `prop under the' rock-arm for automatically propping said 3, arm against a stop-position and supporting said platen in upper-shift position, a second space-bar for operating said escapementmechanism, and an operative connection between said second space-bar and said prop for withdrawing said prop from under said rock-arm to restore the frame to normal low position upon depression of said second space-bar and word-space said group of iigures from an immediately following group of letters.

2. In a typewriting machine of the class described, in combination, a platen-shift mechanism including an operating rock-arm and a locking pin supported by said arm,A

mechanism including a space-bar having connections effective for rockably lifting said arm to raise the platen ofsaid machine, a pivoted locking device on the frame of the machine effective for engaging under said pin after the lifting of the platen, a second space-bar aligned with the first-named spacebar, letter-spacing escapement-mechanism, and a train of mechanism operatively connecting said last-named space-bar and said escapement-meclianism, including a cam-link effective for camming said locking device to ineffective position to release the locked-up platen upon operation of' said last-named space-bar. Y

i 3. The structure described in claim 2, characterized by a construction of said connecting mechanism effective for releasingthe earriage-helding escapement-mechamsm teletterspace the platen after said locking' device is released;

4'. In a typewriting'machine of the class described, the combination with a platenshifting' mechanism, ofa space-bar at the front of the machine, andinterponents be-` tween said space-bar and said mechanism for operating the latter upon depression of said space-bar for letter-'spacing the platen, said interponents including a lever extending from an operative connection with said shift-` ing mechanism toward the front ofthe machine, said leverbeing pivoted intermediate its ends, a cam-roller engaging the forward end of'said lever, and means for moving said roller downwardly against theforward end of said lever upon depression of said spacebar, the forward end of said lever beine" curved upwardly to serve as a stop for sai roller and-also asa am to permit said roller to swing said lever aboutits pivot. p y

`5. In' a typewriting machine of tl'i'eclass described, 4the combination with a platenshift frame and a rock-arm effective for raising' saidshi-ft-frame to upper-case position, of a lever having one end operatively engag-` ing said rock-arm and the other end arranged with a cam-element, a roller engaging said earn-element, a space-bar, and interponents between saidspace-bar and said roller arranged for operatively engaging the latter against said cam-'element to move` said lever about its pivot for swinging said rock-arm :il

and raising said platen."V u i 6.9111 a typewriting machine of theclass described, the Vcombination with a platenshift frame and a rock-'arm effective for' swinging said shift-*frame to its upper-case position, of a forwardly-extending lever having Vits rear end operatively engagingsaid rock-arm' and its front end curved upwardly, a roller disposed against the upper curved side of said lever, a rock-arm on which 'said roller' is mounted,a lateral shaft below said roller` on which said arm is mounted, 'aspacebar, and levers fast on said shaft supporting said spacebar' on their forward ends, whereby the depression of said space-bar is eifective te swing said rollerforwardly and earn tliejcur'v'ed end of said lever down, the positionin of `said shaft, said rock-,arm and curve@ lever-'end being eiectiveto limit the forwardV movement of said roller. 7. The structure described in claim 6, char"- acterized by means normally urging said r'oller' rearwardly, including a stop-member on said" shaft arranged for engagingV againstV a fined elenient ofc said machine to limit the rearward movement of said roller.

iao

iis

` `8.111- a typewritng maehinebhavingfe platen-shift rame,"the combination with a forwardly-extending rock-arm for` raising said shift-frame to its upper-case position,

of means for releasably locking said arm in its uppermost operated position, includm a laterally-extending pin carried by the orward portion of said arm, a locking trigger pivoted below said pin and having an upwardly-extending body and a rearwardlyextendingelbow-member, a spring for urging said trigger forwardly, said trigger-body being positioned whereby its forward edge 1s normally pressed against the back side of said pin, an upwardly and rearwardly sloping locking notch at the junction of said trigger-body in said elbow-member arranged for receiving said pin when the latter is swung upwardly past the front edge of said body, a laterally-extending pin fast to the rearportion of said elbow-member, a' space-bar, and instrumentalities operatively connected with said space-bar and arranged for pressing downwardly on said last-named pin and swingingV said notch out of locking engagement with said last-named pin on depression of said space-bar.

9.- The structure described in claim 8, characterized by an escapement-mechanism, and a forwardly-movable connection between the space-bar and said escapement-mechanism, including a cam, said cam being effective to press downwardly on the pin in the elbowmember.

10. In a typewriting machine having a platen-shift frame, the combination with a forwardly-extending rock-armv for raising said shift-frame to its upper-shift position, of mea-ns for releasably locking said arm in its upper-shifted'position, including a lateral pm carried by the forward portion of said rock-arm, a locking trigger pivoted below said pin and having an upright body and a rearward elbow-member, a spring for urging said trigger against said pin, a locking notch in said trigger-member arranged for receivlng sald pm` a lateral pin fast to said elbowmember, a space-bar, aY case-shifted escapement-mechanism, a forwardly-movable connection between the space-bar andV escapement-mechanism including a cam effective to depress the pin on the elbow-member and withdraw the trigger from under a raised rock-arm pin, and a pivoted dog-rocker operator mounted on the frame and connected to the Vspace-bar-moved connection to vibrate the dog-rocker at either case-shift position thereof to word-space the platen.

11. In a typewriting machine having a shift-frame, in combination, an upwardlymovable operating rock-arm for said shiftframe, a lateral pin supported by said rockarm, a locking trigger arranged to engage under said pin when said arm is moved to its operated position, and means for adjustably positioning said pin transversely to the long axis of said arm, including a plate-member pivotally fastened on a side of said arm and having said pin fastened thereto, and devices for adustably securing said plate to said arm.

l2. In a typewriting machine with an escapement mechanism having an escapement dog rocker, in combina.tion,a vibrator pivotally mounted on the frame of the machine to vibrate said dog rocker, a crank-pin mounted on said vibrator, a pair of space-bars, and a train of mechanism between each space-bar and said vibrator, including a shaft for each space-bar, a crank-arm for each shaft, and a link connecting each crank-arm with the crank-pin on the vibrator, to operate the escapement rocker by either space-bar.

13. In a typewriting machine with an escapementy mechanism having an escapement dog rocker, in combination, a vibrator pivotally vmounted on the frame ofthe machine to vibrate said dog rocker, al crank-pin mounted on said vibrator, a pair of space-bars, and a train of mechanism between each space-bar and said vibrator, including a shaft for each space-bar, a crank-arm for each shaft, and a link connecting each crank-arm with the crank-pin on the vibrator, to operate the escapement rocker by either space-bar, one link having a pin-and-slot connection with one crank-arm, and the other link having a slot connection with said crank-pin, whereby either space-bar is operable to vibrate the escapement rocker by a forward pull on its link without movement-to the other spacebar.

WILLIAM A. DOBSON. 

